The present invention relates to a release liner which serves as a carrier for flat or three-dimensional articles, more particularly, to a release liner having a metal layer incorporated into the release liner and, even more particularly, to a release liner having a metal layer of a sufficient thickness to prevent a laser from penetrating through the metal layer as the article is laser cut. This invention also relates to a method of laser cutting an article releasably attached to such a release liner.
Paper or polymeric release liners are often utilized as carriers for various products. The products are releasably bonded to the release liner because the products are either inherently tacky or coated with an adhesive. The release liner functions as a carrier for the product as well as a protective layer to prevent contamination of either the adhesive or the back side of the product. The release liner is removed and the product is then applied to another object. The products can be flat or three dimensional and may include decorative designs or indicia. The adhesive or tacky surface on the decorative products enable the application and bonding of the decorative product onto another object for display. Examples of such decorative products include nameplates and graphics for automobiles which are applied to a surface of the vehicle, labels which are applied to various surfaces, and decorative films which cling to surfaces such as windows.
The products are often manufactured on the release liner. In order to improve manufacturing efficiency, the products are produced on either large sheets or webs. It then becomes necessary to cut individual parts or portions of the product from the larger production format. In the past, decorative products have been cut from a sheet or web utilizing steel rule cutting devices, often referred to as either die-cutting or kiss-cutting. This process utilizes a sharp edge that mechanically cuts through the product to a desired depth. This type of cut permits the subsequent removal of the cut portion of the product from the release liner for further processing or direct application onto the desired object. The cutting edge of the mechanical cutting devices are metal and therefore difficult to bend into fine shapes or designs. Thus, they are limited in the degree of detail in which they can cut. Additionally, the cost of fabricating a cutting tool to obtain such fine shapes and designs can be very high.
Thus, there is a need to provide a way to cut decorative products attached to a release liner that enables new and more decorative design patterns with improved economics.
The present invention provides a release liner for releasably receiving an article. The release liner is utilized as a carrier sheet during the production or formation of the article. The article is then laser cut into a specific shape or pattern. The release liner of the present invention is able to prevent penetration of the laser through the release liner. Without a metal layer in the release liner, a laser may cut through, or at least partially through, the release liner. The cutting of the release liner can result in the undesirable tearing of the release liner upon removal of a cut portion of the product from the liner. This is particularly a problem when it is preferred to first remove the undesirable portion of the article and leave the portion that will later be removed and applied onto another object. The ability to prevent the penetration of the laser enables the cut portion of the article to be removed from the release liner without a significant portion of the liner tearing and pulling away with the article. Preferably, the release liner is prevented from any tearing when the cut portion of the article is removed.
The release liner of the present invention includes a metal layer with a release agent attached to a side of the metal layer. The release agent is exposed to releasably receive an article. The metal has a thickness sufficient to prevent a laser from penetrating through, and preferably into, the metal layer as the article is laser cut. The metal layer is preferably selected from the group consisting of aluminum, copper, iron, tin, or alloys thereof.
The article applied to the release liner of the present invention can be one or more continuous or discontinuous layers of sheet or web material. The article can be produced from various materials that can be laser cut. Preferred articles include adhesive backed articles and non-adhesive backed articles, such as, for example, vinyl or urethane polymers.
The present release liner may optionally include a support layer affixed to one side of the metal layer opposite the release agent. The support layer can assist in forming a rigid release liner. The thickness of the metal layer can then be minimized to a level sufficient to prevent the penetration of the laser. Alternatively, or in addition, the release liner can optionally include an intermediate layer between the metal layer and the release agent.
The method of the present invention includes laser cutting an article while it is adhered to the release liner.
It is an advantage to provide a release liner that is capable of preventing a laser from penetrating into, or at least through, the liner. A release liner that is capable of withstanding a laser enables laser cutting of an article held directly on the release liner. The cut portion of the article may then be removed from the liner without the liner tearing or a portion of the liner separating with the removed portion of the article.